Shapes Around Us 4th Maths

 

Simple Questions and Answers – Circles, Angles and 3D Shapes

A. Circles

1. What is a circle?
   Answer: A circle is a closed round shape.

2. What is the centre of a circle?
   Answer: The centre is the fixed point in the middle of a circle.

3. What is a radius?
   Answer: A radius is a line segment from the centre to any point on the circle.

4. What is a diameter?
   Answer: A diameter is a line segment passing through the centre and joining two points on the circle.

5. What is a chord?
   Answer: A chord is a line segment joining any two points on a circle.

6. What is the relationship between diameter and radius?
   Answer: Diameter = 2 × Radius.

7. In the diagram, what does OA represent?
   Answer: OA represents the radius.

8. In the diagram, what does AB represent?
   Answer: AB represents the diameter.

9. In the diagram, what does CD represent?
   Answer: CD represents the chord.

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B. Types of Angles

10. What is an acute angle?
    Answer: An angle less than 90° is called an acute angle.

11. Give one example of an acute angle.
    Answer: 45° is an acute angle.

12. What is a right angle?
    Answer: An angle measuring exactly 90° is called a right angle.

13. What is an obtuse angle?
    Answer: An angle greater than 90° but less than 180° is called an obtuse angle.

14. Give one example of an obtuse angle.
    Answer: 100° is an obtuse angle.

15. Is 70° an acute angle?
    Answer: Yes, 70° is an acute angle.

16. Is 90° a right angle?
    Answer: Yes, 90° is a right angle.

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C. 3D Shapes

17. How many faces does a cube have?
    Answer: A cube has 6 faces.

18. How many edges does a cube have?
    Answer: A cube has 12 edges.

19. How many vertices does a cube have?
    Answer: A cube has 8 vertices.

20. How many faces does a cuboid have?
    Answer: A cuboid has 6 faces.

21. How many edges does a cuboid have?
    Answer: A cuboid has 12 edges.

22. How many vertices does a cuboid have?
    Answer: A cuboid has 8 vertices.

23. How many faces does a cone have?
    Answer: A cone has 2 faces.

24. How many edges does a cone have?
    Answer: A cone has 1 edge.

25. How many vertices does a cone have?
    Answer: A cone has 1 vertex.

26. How many faces does a cylinder have?
    Answer: A cylinder has 3 faces.

27. How many edges does a cylinder have?
    Answer: A cylinder has 2 edges.

28. How many vertices does a cylinder have?
    Answer: A cylinder has 0 vertices.

29. How many faces does a sphere have?
    Answer: A sphere has 1 curved face.

30. How many edges and vertices does a sphere have?
    Answer: A sphere has 0 edges and 0 vertices.

31. How many faces does a tetrahedron have?
    Answer: A tetrahedron has 4 faces.

32. How many edges does a tetrahedron have?
    Answer: A tetrahedron has 6 edges.

33. How many vertices does a tetrahedron have?
    Answer: A tetrahedron has 4 vertices.

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D. More 3D Shapes

34. How many faces does a square prism (cube) have?
    Answer: 6 faces.

35. How many vertices does a square prism have?
    Answer: 8 vertices.

36. How many edges does a square prism have?
    Answer: 12 edges.

37. How many faces does a triangular pyramid have?
    Answer: 4 faces.

38. How many vertices does a triangular pyramid have?
    Answer: 4 vertices.

39. How many edges does a triangular pyramid have?
    Answer: 6 edges.

40. How many faces does a square pyramid have?
    Answer: 5 faces.

41. How many vertices does a square pyramid have?
    Answer: 5 vertices.

42. How many edges does a square pyramid have?
    Answer: 8 edges.

43. How many faces does a triangular prism have?
    Answer: 5 faces.

44. How many vertices does a triangular prism have?
    Answer: 6 vertices.

45. How many edges does a triangular prism have?
    Answer: 9 edges.

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Quick Revision

Shape	Faces	Edges	Vertices
Cube	6	12	8
Cuboid	6	12	8
Cone	2	1	1
Cylinder	3	2	0
Sphere	1	0	0
Tetrahedron	4	6	4
Square Pyramid	5	8	5
Triangular Prism	5	9	6